package org.apache.ibatis.demo;

import org.apache.ibatis.executor.Executor;
import org.apache.ibatis.mapping.BoundSql;
import org.apache.ibatis.mapping.MappedStatement;
import org.apache.ibatis.mapping.ParameterMapping;
import org.apache.ibatis.plugin.Interceptor;
import org.apache.ibatis.plugin.Intercepts;
import org.apache.ibatis.plugin.Invocation;
import org.apache.ibatis.plugin.Signature;
import org.apache.ibatis.reflection.MetaObject;
import org.apache.ibatis.session.Configuration;
import org.apache.ibatis.session.ResultHandler;
import org.apache.ibatis.session.RowBounds;
import org.apache.ibatis.type.TypeHandlerRegistry;

import java.text.DateFormat;
import java.util.Date;
import java.util.List;
import java.util.Locale;
import java.util.Properties;
import java.util.regex.Matcher;

/**
 * MyBatis拦截器打印不带问号的完整sql语句
 *
 * @author yincb
 * @version 1.0
 * @date 2021/9/16
 */
@Intercepts({
  @Signature(type = Executor.class, method = "update", args = {MappedStatement.class, Object.class}),
  @Signature(type = Executor.class, method = "query", args = {MappedStatement.class, Object.class, RowBounds.class, ResultHandler.class})
})
public class SqlPrintlnIntercepter implements Interceptor {

  @Override
  public Object intercept(Invocation invocation) throws Throwable {
    MappedStatement mappedStatement = (MappedStatement) invocation.getArgs()[0];
    Object parameter = null;
    if (invocation.getArgs().length > 1) {
      parameter = invocation.getArgs()[1];
      System.out.println("parameter = " + parameter);
    }
    String sqlId = mappedStatement.getId();// 获取到节点的id,即sql语句的id
    System.out.println("sqlId = " + sqlId);
    BoundSql boundSql = mappedStatement.getBoundSql(parameter); // BoundSql就是封装myBatis最终产生的sql类
    Configuration configuration = mappedStatement.getConfiguration(); // 获取节点的配置
    String sql = getSql(configuration, boundSql, sqlId); // 获取到最终的sql语句
    System.out.println("sql = " + sql);
    // 执行完上面的任务后，不改变原有的sql执行过程
    return invocation.proceed();
  }


  @Override
  public Object plugin(Object target) {
    return Interceptor.super.plugin(target);
  }

  @Override
  public void setProperties(Properties properties) {
    Interceptor.super.setProperties(properties);
  }


  // 封装了一下sql语句，使得结果返回完整xml路径下的sql语句节点id + sql语句
  private String getSql(Configuration configuration, BoundSql boundSql, String sqlId) {
    String sql = showSql(configuration, boundSql);
    StringBuilder str = new StringBuilder(100);
    str.append(sqlId);
    str.append(":");
    str.append(sql);
    return str.toString();
  }

  // 进行？的替换
  private String showSql(Configuration configuration, BoundSql boundSql) {
    // 获取参数
    Object parameterObject = boundSql.getParameterObject();
    List<ParameterMapping> parameterMappings = boundSql.getParameterMappings();
    // sql语句中多个空格都用一个空格代替
    String sql = boundSql.getSql().replaceAll("[\\s]+", " ");
    if ((parameterMappings != null && parameterMappings.size() > 0) && parameterObject != null) {
      // 获取类型处理器注册器，类型处理器的功能是进行java类型和数据库类型的转换
      TypeHandlerRegistry typeHandlerRegistry = configuration.getTypeHandlerRegistry();
      // 如果根据parameterObject.getClass(）可以找到对应的类型，则替换
      if (typeHandlerRegistry.hasTypeHandler(parameterObject.getClass())) {
        sql = sql.replaceFirst("\\?", Matcher.quoteReplacement(getParameterValue(parameterObject)));
      } else {
        // MetaObject主要是封装了originalObject对象，提供了get和set的方法用于获取和设置originalObject的属性值,主要支持对JavaBean、Collection、Map三种类型对象的操作
        MetaObject metaObject = configuration.newMetaObject(parameterObject);
        for (ParameterMapping parameterMapping : parameterMappings) {
          String propertyName = parameterMapping.getProperty();
          if (metaObject.hasGetter(propertyName)) {
            Object obj = metaObject.getValue(propertyName);
            sql = sql.replaceFirst("\\?", Matcher.quoteReplacement(getParameterValue(obj)));
          } else if (boundSql.hasAdditionalParameter(propertyName)) {
            // 该分支是动态sql
            Object obj = boundSql.getAdditionalParameter(propertyName);
            sql = sql.replaceFirst("\\?", Matcher.quoteReplacement(getParameterValue(obj)));
          } else {
            // 打印出缺失，提醒该参数缺失并防止错位
            sql = sql.replaceFirst("\\?", "缺失");
          }
        }
      }
    }
    return sql;
  }

  // 如果参数是String，则添加单引号， 如果是日期，则转换为时间格式器并加单引号； 对参数是null和不是null的情况作了处理
  private String getParameterValue(Object obj) {
    String value = null;
    if (obj instanceof String) {
      value = "'" + obj.toString() + "'";
    } else if (obj instanceof Date) {
      DateFormat formatter = DateFormat.getDateTimeInstance(DateFormat.DEFAULT,
        DateFormat.DEFAULT, Locale.CHINA);
      value = "'" + formatter.format(new Date()) + "'";
    } else {
      if (obj != null) {
        value = obj.toString();
      } else {
        value = "";
      }

    }
    return value;
  }


}
